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21.
A recent meta-analysis from the Antiplatelet Trialists'' Collaboration recommended that antilatelet treatment either alone or, for greater effect, in addition to other proved forms of thromboprophylaxis should be considered for patients at high risk of thromboembolism. This paper argues that the current evidence does not justify the adoption of aspirin or other antiplatelet treatment for venous thromboprophylaxis, especially when more effective alternatives exist. Furthermore, several issues relating to this latest meta-analysis need to be debated.  相似文献   
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A dot-ELISA technique for the detection of Pseudomonas protease was developedusing IgG of anti- Pseudomonas AFT-36 protease as capture antibody. The detection limitof protease in buffer or milk was 1·01 ng ml−1. The procedure was performedat room temperature, took about 2·5 h and was economical. Protease AFT-36 isimmunologically related to five out of seven Pseudomonas spp. The results suggest thatthe assay could be used to detect proteases in dairy products.  相似文献   
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The conditions to obtain materials with elastic-viscous properties based on chitosan succinamide have been studied. A decreased polymer content and a transition from visco-elastic liquids to elastic-viscous systems were shown upon the addition of glycerol to an aqueous solution of chitosan succinamide. The systemic response, biological compatibility, and dynamics of bioresorbability of the obtained materials were studied during implantation in laboratory animals.  相似文献   
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Bacteriomorphic organisms found in fruits of capitate infructescences in Kunduricarpus Kodrul, N. Maslova, Tekleva et Golovneva, Platanaceae, are described. Three types of carpel damage have been detected: (1) evidence of penetration of microorganisms in the walls of the carpel, (2) three-dimensional structures (isolated and in chains) rounded in section, which fill the inner space of the carpel, and (3) imprints of these structures on the inner surface of the carpel wall cuticle. The possible nature of the microorganisms is discussed.  相似文献   
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Increasing sand temperatures resulting from climate change may negatively impact sea turtle nests by altering sex ratios and decreasing reproductive output. We analyzed the effect of nest shading and watering on sand temperatures as climate mitigation strategies in a beach hatchery at Playa Grande, Costa Rica. We set up plots and placed thermocouples at depths of 45cm and 75cm. Half of the plots were shaded and half were exposed to the sun. Within these exposure treatments, we applied three watering treatments over one month, replicating local climatic conditions experienced in this area. We also examined gravimetric water content of sand by collecting sand samples the day before watering began, the day after watering was complete, and one month after completion. Shading had the largest impact on sand temperature, followed by watering and depth. All watering treatments lowered sand temperature, but the effect varied with depth. Temperatures in plots that received water returned to control levels within 10 days after watering stopped. Water content increased at both depths in the two highest water treatments, and 30 days after the end of water application remained higher than plots with low water. While the impacts of watering on sand temperature dissipate rapidly after the end of application, the impacts on water content are much more lasting. Although less effective at lowering sand temperatures than shading, watering may benefit sea turtle clutches by offsetting negative impacts of low levels of rain in particularly dry areas. Prior to implementing such strategies, the natural conditions at the location of interest (e.g. clutch depth, environmental conditions, and beach characteristics) and natural hatchling sex ratios should be taken into consideration. These results provide insight into the effectiveness of nest shading and watering as climate mitigation techniques and illustrate important points of consideration in the crafting of such strategies.  相似文献   
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